The present invention generally relates to mowing machines. More specifically, the present invention relates to mowing machines which include ergonomic hand control levers which can reduce or eliminate certain anatomical stress associated with the operation of such mowing machines.
Self-propelled mowing machines are well known. Certain self-propelled mowing machines include two hand control levers, each of which is separately associated with a drive wheel. By manipulating the hand control levers, a user can control the speed and direction of the mowing machine.
As illustrated in FIG. 1, an existing lever-operated mowing machine has hand control levers 10 which are substantially perpendicular to the mowing machine's travel line 12. The hand control levers 10 move in a forward and backward line of direction. The user pushes and pulls the hand control levers 10 along the force lines 16 and 18. The push/pull action is indicated by arrows 16a and 18a. 
Typically, when the user pushes or pulls the hand control levers 10 forward or backward, at some point the user moves his/her elbows apart from his/her body. When the elbow is obviated from the body, the wrists 14 and hands 20 become radially deviated. In other words, the wrists 14 and hands 20 are rotated counterclockwise in a plane horizontal to the driving surface. This radial deviation can form: (a) a wrist angle 22 between the force line 16 and the forearm axis 24; and (b) a wrist angle 22 between the force line 18 and the forearm axis 26. Pushing and pulling the hand control levers 10 at this wrist angle can create anatomical stress in the user's wrists 14, hands, arms and other parts of the body.
No commercial mowing machines are known to have hand control levers which are ergonomically configured to reduce the user's anatomical stress, fatigue or discomfort caused by operating the hand control levers. This can be especially problematic in lever-operated mowing machines because of the user's need to continuously hold the hand control levers over a prolonged period of time in order to keep the mowing machine traveling at a desired speed with a desired direction. Therefore, there is a need to overcome these disadvantages.